An electric apparatus mounted on an automobile or the like forms an electric circuit by connecting such an electric apparatus with another electric apparatus or a power source device through a wire harness which is formed by binding insulated wires. In this case, the wire harness is connected with the electric apparatus or the power source device by connecting connectors which are mounted on these components by female-male fitting engagement. A connection structural body where a crimp terminal is connected to an insulated wire by pressure-bonding connection is mounted in the above-mentioned connector.
The connection structural body is configured such that the insulated wire is inserted into the crimp terminal having a pressure-bonding section to which a conductor of the insulated wire is electrically connected and, thereafter, the pressure-bonding section is caulked thus connecting the crimp terminal and the insulated wire to each other in a conductive manner.
Recently, electrical components are required to have multiple functions and high performance. To satisfy such requirements, electric circuits are becoming more and more complicated, and the more reliable conductivity is required at a pressure-bonding connecting section between each crimp terminal and an insulated wire. Accordingly, when a conventional open-barrel-type crimp terminal is used, a pressure-bonding section and a conductor are exposed and hence, a surface of the pressure-bonding section or a surface of the conductor in the pressure-bonding connecting section may be corroded under a severe in-use environment, thus giving rise to a possibility that conductivity is lowered.
To cope with such a drawback, for example, with the use of a crimp terminal provided with a closed-barrel-type pressure-bonding section which is described in paragraph [0006] of Patent Document 1, it is possible to provide the connection structural body capable of preventing corrosion which occurs on a surface of a pressure-bonding section or on a surface of a conductor in a pressure-bonding connecting section.
As such a closed-barrel-type crimp terminal, there is a crimp terminal disclosed in Patent Document 2, for example. As disclosed in FIG. 11 to FIG. 16 of Patent Document 2, the crimp terminal disclosed in Patent Document 2 is provided with a cylindrical pressure-bonding section in one end thereof in the long length direction, with the other end closed. It is considered that, by inserting and pressure-bonding a tip end of an insulated wire to the cylindrical pressure-bonding section, the reliable conduction between the crimp terminal and a conductor of the insulated wire can be acquired and, at the same time, it is possible to prevent corrosion which may occur on a surface of the pressure-bonding section or a surface of the conductor in the pressure-bonding connecting section.
However, to satisfy a demand for reduction of weight and space saving of recent years, a crimp terminal per se is miniaturized and hence, it has been difficult to confirm a pressure-bonded state which realizes reliable conductivity at a manufacturing stage including the insertion of a wire tip into a pressure-bonding section and the pressure bonding of the pressure-bonding section to the wire tip.